Method of treating septic shock using thymosin-α 1

ABSTRACT

A method of reducing toxicity of endotoxin in a mammal including the administration of an endotoxin-reducing effective amount of Tα 1  to the mammal.

BACKGROUND OF THE INVENTION CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. patent application Ser. No. 08/132,859, filed Oct. 7, 1993, abandoned.

FIELD OF THE INVENTION

The present invention relates to a method of treating septic shock in mammals.

DESCRIPTION OF BACKGROUND ART

Thymosin α₁ ("Tα₁ ") is a peptide originally derived from the Thymus gland, which has been reported as containing 28 amino acids. Amino acid sequence information on Tα₁ is disclosed in U.S. Pat. No. 4,079,127, incorporated herein by reference.

Tα₁ is an immune system modulator which heretofore has been reported as being useful, inter alia, in the treatment of lung cancer, Hepatitis B and Hepatitis C.

Septic shock is a condition in which infection is widely disseminated in many areas of the body, the infection generally being disseminated through the blood from one tissue to another and causing extensive damage. Septic shock can occur with numerous medical conditions, including (1) peritonitis caused by the spread of infection from the uterus and fallopian tubes; (2) peritonitis resulting from rupture of the gut, sometimes caused by intestinal disease or wounds; (3) generalized infection resulting from spread of a simple infection; (4) generalized gangrenous infection resulting specifically from gas gangrene bacilli; and (5) infection spreading into the blood from the kidney or urinary tract. Septic shock is of critical concern from a clinical viewpoint because, among other reasons, this condition frequently leads to death.

Although septic shock is a somewhat common clinical phenomenon, the mechanisms involved as well as the pathological changes remain poorly understood. For example, despite the treatment of bacterial infection, many patients deteriorate further, which may be due to clinical sequelae of hypotension with low systemic vascular resistance, renal insufficiency, adult respiratory distress syndrome, severe coagulopathy and severe metabolic dysfunctions. Thus, there is an urgent need in the art for effective methods of treating septic shock.

SUMMARY OF THE INVENTION

In accordance with the present invention, a method of treating septic shock in mammals includes administering a septic shock-treating effective amount of Tα₁ to said mammals.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

It surprisingly has been discovered that Thymosin α₁ (Tα₁) is effective in treating or preventing septic shock or sepsis in mammals. This discovery was surprising, because Thymosin α₁ was expected to be without activity with respect to septic shock when initially tested.

The terms "Thymosin α₁ " and "Tα₁ " refer to peptides having the amino acid sequence disclosed in U.S. Pat. No. 4,079,137, supra.

Mammalian septic shock occurs in association with a series of events in the mammal's body referred to as the "sepsis cascade". The sepsis cascade typically begins with bacterial infection of the mammalian host resulting in release of bacterial toxins, introduction of endotoxin, activiation of host defense systems, i.e., plasma protein systems as well as cellular defense systems including endothelial cells, macrophages, monocytes and neutrophils, with release of proinflammatory mediators including cytokines, lipid metobolites, proteases, toxic oxygen products, nitric oxide and adhesion proteins.

According to one aspect of the present invention, effective amounts of Tα₁ are administered to a subject to reduce blood free radical levels in the subject, and thereby treat or prevent septic shock in the subject or obstruct progression of sepsis cascade in the subject. Tα₁ has been found to reduce blood free radical levels almost as much as SOD (super oxide dismutase), an enzyme that eliminates free radicals. When a septic shock-treating or a septic shock-preventing effective amount of Tα₁ is administered to a mammal, the blood levels of pathological mediators of bacteria-induced lethality are decreased in the mammal.

Tα₁ has been found to obstruct the sepsis cascade in mammals. During sepsis, peroxidation of lipids in blood is increased (mMol of malonyldialdehyde), but returned to normal or about normal with Tα₁ administration. Sepsis also reduces circulating blood leves of glutathione. However, administration of Tα₁ returns circulatory gluthathine leves to normal or about normal.

As noted above, administration of Tα₁ during sepsis decreases blood hydroperoxide levels and increases blood glutathione levels. Administration of Tα₁ during sepsis also decreases cerebellar cGMP levels, and decreases the blood levels of arachidonic acid metabolites such as Txβ₂ and 6-keto-PGF₁ α, PAF, and cytokines such as IL-1α and TNF-α.

While not wishing to be bound to any particular theory, it is believed that reducing blood levels of pathological mediators of bacteria-induced lethality in a mammal decreases the amount of infection in the mammal which, in turn, aids in obstructing the spesis cascade, and in preventing and treating septic shock.

Thus, according to the present invention, methods of treating and preventing septic shock in mammals are provided. The methods of the present invention include administration of septic shock-treating effective amounts, septic shock-preventing effective amounts and sepsis cascade progression-obstructing effective amounts of Tα₁ to mammals.

According to preferred embodiments of the present invention, effective amounts of Tα₁ are administered to subjects to treat or prevent septic shock in the subjects, or obstruct progression of sepsis cascade in the subjects. In these embodiments, the subjects preferably are human.

According to preferred embodiments of the present invention, compositions containing Tα₁ may be formulated in a conventional manner for administration by any suitable route. Suitable routes of administration include, but are not limited to, oral, rectal, nasal, topical, vaginal, and parenteral (including subcutaneous, intramuscular, intravenous and intradermal). Particularly preferred embodiments utilize oral or parenteral administration, with parenteral administration being a more preferred embodiment. It will be appreciated that the preferred route may vary with the condition, age and species of the recipient.

While not essential, in preferred embodiments, Tα₁ is administered as part of a pharmaceutical formulation. The formulations of the present invention comprise Tα₁ together with one or more pharmaceutically acceptable carriers and optionally with other therapeutic ingredients. The carrier(s) are "acceptable" in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient thereof.

The formulations include those suitable for oral, rectal, nasal, topical (including buccal and sublingual), vaginal or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration. The formulations may conveniently be presented in unit dosage form, e.g., tablets and sustained release capsules, and may be prepared by any suitable pharmaceutical methods.

Such methods include, but are not limited to, the step of bringing into association Tα₁ with the carrier which constitutes one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing into association Tα₁ with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product.

Formulations of the present invention suitable for oral administration may be presented as discrete units such as capsules, cachets or tablets each containing a predetermined amount of Tα₁, as a powder or granules; as a solution or a suspension in an aqueous liquid or a non-aqueous liquid; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion, etc.

A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine Tα₁ in a free-flowing form such as a powder or granules, optionally mixed with a binder, lubricant, inert diluent, preservative, surface-active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may optionally be coated or scored and may be formulated so as to provide slow or controlled release of the active ingredient therein.

Formulations suitable for topical administration include lozenges comprising Tα₁ in a flavored basis, usually sucrose and acacia or tragacanth; pastilles comprising Tα₁ in an inert basis such as gelatin and glycerin, or sucrose and acacia; and mouthwashes comprising Tα₁ to be administered in a suitable liquid carrier.

Formulations suitable for topical administration to the skin may be presented as ointments, creams, gels and pastes comprising Tα₁ and a pharmaceutically acceptable carrier, or may utilize a transdermal patch containing the ingredient to be administered.

Formulations for rectal administration may be presented as a suppository with a suitable base comprising, for example, cocoa butter or a salicylate.

Formulations suitable for nasal administration wherein the carrier is a solid include a coarse powder having a particle size, for example, in the range from about 20 to about 500 microns which is administered in the manner in which snuff is taken, i.e., by rapid inhalation through the nasal passage from a container of the powder held close up to the nose. Suitable formulations wherein the carrier is a liquid, for administration, as for example, a nasal spray or as nasal drops, include aqueous or oily solutions of the active ingredient.

Formulations suitable for vaginal administration may be presented as tampons, creams, gels, pastes, foams or spray formulations containing, in addition to Tα₁, suitable carriers.

Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may optionally contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example, sealed ampules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described.

It should be understood that in addition to the ingredients particularly mentioned above the formulations of this invention may include other suitable agents having regard to the type of formulation in question, for example, those suitable for oral administration may include flavoring agents.

A dose for administration of the compositions in the present invention is a septic shock-treating or a septic shock-preventing effective amount of Tα₁, which can be in a range of from about 0.4 mg to about 4 mg of Tα₁ per kg of body weight of recipient (mg/kg), preferably from about 1 to about 4 mg/kg. A dose can be administered to the patient daily, one or more times per day of administration, e.g., two or three times per day, and doses can be administered one or more days per week, e.g., two, three, four, five, six or seven days per week.

The invention is applicable to native (i.e., naturally occurring) Tα₁, as well as synthetic Tα₁ and recombinant Tα₁ having the amino acid sequence of native Tα₁, amino acid sequences substantially similar thereto, or an abbreviated sequence form thereof, and their biologically active analogs (including muteins) having substituted, deleted, elongated, replaced, or otherwise modified sequences which possess bioactivity substantially similar to that of Tα₁.

In accordance with one embodiment of the present invention, Tα₁ can be administered in combination with a therapeutically effective amount of another substance useful in treating septic shock such as, for example, antibiotics, or antibodies (polyclonal or monoclonal) directed to antigens located on endotoxins. Of course, the acceptable dosage range of the other substance will depend upon its properties (i.e., the acceptable dosage range will depend upon what other substance is being administered).

Tα₁ and another substance useful in preventing or treating septic shock can be administered "in combination" which, as defined herein, includes various schemes designed to administer Tα₁ and the other substance to a subject, whether or not the other substance and Tα₁ are administered separately or together, such that the desired dosages of Tα₁ and the other substance are present in the subject at the same time. Any suitable scheme can be used to administer Tα₁ and another substance useful in preventing or treating septic shock "in combination" in accordance with the present invention.

Suitable dosages of either Tα₁ alone or Tα₁ in combination with another substance useful in treating or preventing septic shock may be administered 1 to 3 times or more per day. The precise dose administered will depend on the age, condition and other factors of the recipient.

The following examples are for illustrative purposes only, and are not to be construed in a limiting sense.

EXAMPLE 1

Synthetic Tα₁ was provided by Alpha 1 Biomedicals, Inc. (Two Democracy Center, 6903 Rockledge Drive, Ste. 1200, Bethesda, Md. 20817). Tα₁ was prepared by solid phase peptide synthesis.

Swiss-Webster mice 4-6 weeks of age (20-25 g) were divided into 2 groups: endotoxic mice (endotoxin 60 mg/kg i.p. in acute treatment) and endotoxic mice treated with 3 injections of 100 μg Tα₁ (5 minutes, 2 and 4 hours post administration of the endotoxin).

The results presented in Tables I and II below indicate that Tα₁ administered 3 times post administration of endotoxin increased the survival rate of mice treated with endotoxin to 100%.

The results presented in Tables III-VII below show effects of Tα₁ respectively on mice blood malonyldialdehyde levels, glutathione levels, cerebellar cGMP levels, blood serum TNF-α levels, and blood serum TNF-α and IL-1α levels.

                  TABLE I                                                          ______________________________________                                         Survival of Swiss Webster Mice Following Lethal                                Endotoxin Dose and Tα.sub.1                                                              Number of Mice Alive                                           EXPERIMENTAL GROUPS                                                                              0 hrs  24 hrs  48 hrs                                                                               72 hrs                                  ______________________________________                                         Endotoxin 60 mg/kg                                                                               7      1       1     1                                       Endotoxin 60 mg/kg +                                                                             7      7       7     7                                       Tα.sub.1 100 μg 3×                                              ______________________________________                                    

                  TABLE II                                                         ______________________________________                                         Protective Effect of Tα.sub.1 on Survival of Mice Treated with           Lethal Doses of Endotoxin                                                                      Number of Mice Alive                                                             0      24    48  72  7    14                                 EXPERIMENTAL GROUPS                                                                              hr.    hr.   hr. hr. day  day                                ______________________________________                                         Endotoxin 60 mg/kg                                                                               8      0                                                     Endotoxin 60 mg/kg +                                                                             8      8     8   8   8    8                                  Tα.sub.1 100 μg 3×                                              ______________________________________                                    

                  TABLE III                                                        ______________________________________                                         The effects of Tα.sub.1 on changes in blood hydroperoxide                levels after treating the mice with lethal                                     doses of endotoxin                                                                              Blood levels of                                               EXPERIMENTAL GROUPS                                                                             malonyldialdehyde (nMol MDA)                                  ______________________________________                                         Control          17.5 ± 1.2                                                 Endotoxin 60 mg/kg                                                                              38.2 ± 2.9                                                 Endotoxin 60 mg/kg +                                                                            16.9 ± 1.36                                                Tα.sub.1 100                                                             ______________________________________                                          *Whole blood samples (0.5 ml) were obtained by tail bleds 1 hour after         endotoxin administration                                                 

                  TABLE IV                                                         ______________________________________                                         The effects of Tα.sub.1 gluthathione levels in mice                      treated with lethal doses of endotoxin                                         EXPERIMENTAL GROUPS                                                                              RBC GSH (μmoles/ml cells)*                                ______________________________________                                         Control           1.25 ± 0.09                                               Endotoxin 60 mg/kg                                                                               0.61 ± 0.05                                               Endotoxin 60 mg/kg +                                                                             1.12 ± 0.12                                               Tα.sub.1 100 μg/mouse                                                 ______________________________________                                          *Total erythrocyte glutathione, 98% of which is in the reduced form (GSH)      was determined by the enzymatic "cyclic method."-                        

                  TABLE V                                                          ______________________________________                                         Tα.sub.1 effects on cGMP cerebellar levels in mice                       treated with lethal doses of endotoxin                                                           Cerebellar cortex cyclic GMP                                 EXPERIMENTAL GROUPS                                                                              (pmol per mg/protein)                                        ______________________________________                                         Control           10.1 ± 0.2                                                Endotoxin 60 mg/kg                                                                               30.7 ± 4.1                                                i.p.                                                                           Endotoxin 60 mg/kg                                                                               14.6 ± 1.2                                                i.p. + Tα.sub.1 100 μg                                                ______________________________________                                    

                  TABLE VI                                                         ______________________________________                                         Serum TNF-α levels in mice treated with                                  lethal doses of endotoxin                                                                      TNF-α (pg/ml)                                            EXPERIMENTAL GROUPS                                                                              1 hr     3 hr     5 hr                                       ______________________________________                                         Endotoxin 60 mg/kg                                                                               1098 ±                                                                               783 ± 38                                                                             623 ± 51                                                  106                                                          Endotoxin 60 mg/kg +                                                                             638 ± 57                                                                             426 ± 37                                                                             297 ± 27                                Tα.sub.1                                                                 ______________________________________                                    

                  TABLE VII                                                        ______________________________________                                         Serum TNF-α and IL-1α levels* in mice protected against            endotoxin-induced lethality by pretreatment with SOD and Tα.sub.1        Pretreatment    TNF-α (pg/ml)                                                                         IL-1 α (pg/ml)                              ______________________________________                                         None            4462 ± 123                                                                               1137 ± 123                                     SOD (3.3 × 10.sup.4 μ/kg)                                                             63 ± 5.1  53 ± 3.1                                       Tα.sub.1 100 μg/mice                                                                  285 ± 23.6                                                                               109 ± 71                                       ______________________________________                                          *Mice were pretreated with SOD (super oxide dismatase), 30 minutes before      endotoxin administration XX blood for determined of TNFα and             IL1α levels was collected 1 hr after endotoxin administration.     

EXAMPLE 2

Using the same materials and methods as in example 1, the time and dose-dependency of the protective effect of Tα₁ on endotoxin lethality were studied. The results are presented in Table VIII below.

As can be seen in Table VIII, Tα₁ had protective effect on endotoxin toxicity when given immediately following, 2 and 4 hours after endotoxin treatment or when given 2, 4 and 6 hours after endotoxin treatment. The effective protective dose was 100 μg Tα₁ administered three times.

                                      TABLE VIII                                   __________________________________________________________________________     Survival of Swiss Webster Mice Following Lethal Endotoxin Dose and             Tα.sub.1                                                                              Number of Mice Alive                                              Experimental Groups                                                                         0 hrs                                                                             24 hrs                                                                              48 hrs                                                                             72 hrs                                                                              96 hrs                                                                             120 hrs                                      __________________________________________________________________________     Endotoxin 60 mg/kg                                                                          8  4    4   4    4   4                                            Endotoxin 60 mg/kg +                                                                        8  8    8   8    8   8                                            Tα.sub.1 100 μg, 3×;                                            Tα.sub.1 was admini-                                                     stered immediately                                                             following, 2 and                                                               4 hrs. after endo-                                                             toxin.                                                                         Endotoxin 60 mg/kg +                                                                        8  8    8   8    8   8                                            Tα.sub.1 100 μg, 3×;                                            Tα.sub.1 was admini-                                                     stered 2, 4 and 6                                                              hrs. after endo-                                                               toxin.                                                                         Endotoxin 60 mg/kg +                                                                        8  8    5   5    5   5                                            Tα.sub.1 10 μg, 3×;                                             Tα.sub.1 was admini-                                                     stered immediately                                                             following, 2 and                                                               4 hrs. after endo-                                                             toxin.                                                                         __________________________________________________________________________

EXAMPLE 3

Using the same methods and materials as in examples 1 and 2, the effect which Tα₁ has on blood levels of IL-1α, TNF-α, PAG, Txβ₂ and 6-keto-PGF₁ α, which are pathological mediators of endotoxin induced lethality, was studied. The results are presented in Tables IX-XIV below.

As can be seen in Tables IX-XIV, Tα₁ decreased IL-1α, TNF-α serum levels as well as PAF, Txβ₂ and 6-keto-PGF₁ α plasma levels after administration of a lethal dose of endotoxin.

                  TABLE IX                                                         ______________________________________                                                          IL-1α pg/ml (serum levels)                              EXPERIMENTAL GROUPS                                                                               1 hr       3 hr                                             ______________________________________                                         Endotoxin 60 mg/kg 492 ± 45.2                                                                             550 ± 37.1                                    Endotoxin 60 mg/kg +                                                                              83 ± 7.1                                                                               165 ± 13.7                                    Tα.sub.1 100 μg administered                                          immediately following                                                          ______________________________________                                    

                  TABLE X                                                          ______________________________________                                         EXPERIMENTAL PAF (pg/ml) (plasma levels)                                       GROUPS       0.5 hr  1 hr      2 hr   3 hr                                     ______________________________________                                         Endotoxin 60 78 ± 6                                                                              279 ± 17                                                                              127 ± 13                                                                           55 ± 3                                mg/kg                                                                          Endotoxin 60 48 ± 3                                                                              136 ± 9                                                                               68 ± 4                                                                             32 ± 2                                mg/kg + Tα.sub.1                                                         100 μg admin-                                                               istered                                                                        immediately                                                                    following                                                                      ______________________________________                                    

                  TABLE XI                                                         ______________________________________                                         EXPERIMENTAL T × β.sub.2 (pg/ml) (plasma levels)                    GROUPS       0.5 hr.  1 hr     2 hr   3 hr                                     ______________________________________                                         Endotoxin 60 1442 ±                                                                               2937 ±                                                                               912 ±                                                                              695 ±                                 mg/kg        103      258      105    65                                       Endotoxin 60 910 ± 85                                                                             1921 ±                                                                               530 ± 47                                                                           391 ±                                 mg/kg + Tα.sub.1                                                                               185             260                                      100 μg admin-                                                               istered                                                                        immediately                                                                    following                                                                      ______________________________________                                    

                  TABLE XII                                                        ______________________________________                                         EXPERIMENTAL                                                                               6-keto-PGF1α (pg/ml) (plasma levels)                         GROUPS      0.5 hr.  1 hr      2 hr   3 hr                                     ______________________________________                                         Endotoxin 60                                                                               341 ± 31                                                                             1141 ± 112                                                                            897 ± 75                                                                           811 ± 7                               mg/kg                                                                          Endotoxin 60                                                                               224 ± 19                                                                             745 ± 62                                                                              341 ± 33                                                                           205 ± 19                              mg/kg + Tα.sub.1                                                         100 μg admin-                                                               istered                                                                        immediately                                                                    following                                                                      ______________________________________                                    

                  TABLE XIII                                                       ______________________________________                                                          PAF (pg/ml) (serum levels)                                    EXPERIMENTAL GROUPS                                                                               1 hr      3 hr   5 hr                                       ______________________________________                                         Endotoxin 60       938       662    567                                        mg/kg                                                                          Endotoxin 60       783       508    429                                        mg/kg + Tα.sub.1                                                         100 μg admin-                                                               istered                                                                        immediately                                                                    following                                                                      ______________________________________                                    

                  TABLE XIV                                                        ______________________________________                                                          TNF-α (pg/ml)                                                            (serum levels)                                                EXPERIMENTAL GROUPS                                                                               1 hr      3 hr   5 hr                                       ______________________________________                                         Endotoxin 60       938       662    567                                        mg/kg                                                                          Endotoxin 60       783       508    429                                        mg/kg + Tα.sub.1                                                         100 μg admin-                                                               istered                                                                        immediately                                                                    following                                                                      ______________________________________                                    

EXAMPLE 4

Using a septic shock model in rats (Sprague-Dawley, male, 200-225 g each), the effect of thymosin α₁ alone and together with antibiotics was studied. Peritonitis was induced in rats in the following way. A 1-cm incision was made into the peritoneal which exposed the cecum. A tight ligature was placed around the cecum with 4-0 suture distal to the insertion of the small bowel, forming an area of devitalized tissue while maintaining bowel continuity. A puncture wound was made with 16-gauge needle into the anti-mesenteric surface of the cecum and a small amount of fecal contents was expressed through the wound. The cecum was replaced into the peritoneal cavity, and the anterior peritoneal wall and skin were closed with surgical staples. Each animal was given a bolus of normal saline (15 ml/kg) for hydration and allowed to recover overnight.

The results presented in Table XV show Tα₁ increased the survival of rats.

                  TABLE XV                                                         ______________________________________                                         Survival of Sprague-Dawley rats following septic                               shock, antibiotics, and thymosin α.sub.1                                 EXPERIMENTAL GROUPS                                                                             0 hr    24 hr   48 hr 72 hr                                   ______________________________________                                         Rats with peritonitis +                                                                         10      1       1     0                                       antibiotic*                                                                    Rats with peritonitis +                                                                         10      8       6     6                                       antibiotic* + thymosin                                                         α.sub.1 1 mg/rat × 3**                                             ______________________________________                                          *gentamicin sulfate, 1 mg/rat                                                  **At 0 hr, 2 hr, and 4 hr post induction of peritonitis                  

The results presented in Tables XVI to XIX below show effects of Tα₁ respectively on rat cytokine levels, blood malonyldialdehyde levels, glutathione levels and arachidonic acid metabolic levels.

                  TABLE XVI                                                        ______________________________________                                         The effect of Tα.sub.1 on Cytokine Levels                                in a septic shock model in rat                                                 EXPERIMENTAL GROUPS                                                                              TNFα (pg/ml)                                                                         IL.sub.1 α (pg/ml)                         ______________________________________                                         Control           undetectable                                                                               undetectable                                     Rats with Septic  2658 ± 197                                                                              1387 ± 123                                    Shock                                                                          Rats with Septic  1231 ± 129                                                                              689 ± 53                                      Shock + Tα.sub.1 1 mg/rat ×                                        3 as above                                                                     ______________________________________                                    

                  TABLE XVII                                                       ______________________________________                                         The effect of Tα.sub.1 on lipid peroxidation in                          a septic shock model in rat                                                                        Blood Levels of malonyl-                                   EXPERIMENTAL GROUPS dialdehyde (nNol MDA)                                      ______________________________________                                         Control             15.3 ± 1.3                                                                             18.6 ± 1.1                                   Rats with Septic    49.1 ± 3.5                                                                             46.3 ± 3.8                                   Shock                                                                          Rats with Septic +  17.1 ± 1.6                                                                             21.9 ± 2.3                                   Tα.sub.1 1 mg/rat ×                                                3 as above                                                                     ______________________________________                                    

                  TABLE XVIII                                                      ______________________________________                                         The effect of Tα.sub.1 on glutathione levels                             in a rat septic shock model                                                    EXPERIMENTAL GROUPS                                                                              RBC GSH (μmoles/ml cells)                                 ______________________________________                                         Control           1.38 ± 0.1                                                                             1.46 ± 0.13                                    Rats with Septic Shock                                                                           0.43 ± 0.05                                                                            0.29 ± 0.04                                    Rats with Septic Shock +                                                                         1.29 ± 0.07                                                                            1.20 ± 0.085                                   Tα.sub.1 mg/rat × 3 as                                             above                                                                          ______________________________________                                    

                  TABLE XIX                                                        ______________________________________                                         The effect of Tα.sub.1 on arachidonic acid metabolite                    levels in a septic shock model in rat                                                           6-keto-PGF.sub.1                                              EXPERIMENTAL GROUPS                                                                             (pg/ml)    T × β.sub.2, (pg/ml)                    ______________________________________                                         Control          58 ± 3.5                                                                               89 ± 7.6                                        Rats with Septic Shock                                                                          1828 ± 145.3                                                                           3622 ± 295                                      Rats with Septic Shock +                                                                        1132 ± 96                                                                              2353 ± 197                                      Tα.sub.1 1 mg/rat × 3 as                                           above                                                                          ______________________________________                                    

The results presented in Tables XX and XXI below demonstrate that Tα₁ increases the survival rate of rats with septic shock.

                  TABLE XX                                                         ______________________________________                                                         Number of Rats Alive                                           EXPERIMENTAL GROUPS                                                                              0 h    24 h    48 h  72 h                                    ______________________________________                                         Rats with Septic Shock                                                                           10     2       2     0                                       Rats with Septic Shock +                                                                         10     9       9     5                                       Tα.sub.1 1 mg/rat × 3                                              as above                                                                       ______________________________________                                    

                  TABLE XXI                                                        ______________________________________                                                         Number of Rats Alive                                           EXPERIMENTAL GROUPS                                                                              0 h    24 h    48 h  72 h                                    ______________________________________                                         Rats With Septic Shock                                                                           10     1       0     0                                       Rats with Septic Shock +                                                                         10     8       7     3                                       Tα.sub.1 1 mg/rat × 3                                              as above                                                                       ______________________________________                                    

While the invention has been described and illustrated with details and references to certain preferred embodiments, those skilled in the art will appreciate that various modifications, changes, omissions, and substitutes can be made without departing from the spirit of the invention. 

What is claimed is:
 1. A method of reducing toxicity of endotoxin in a mammal following endotoxin introduction in said mammal, comprising administering to said mammal an endotoxin-reducing effective amount of Tα₁.
 2. The method of claim 1, wherein said amount of Tα₁ is sufficient to reverse in said mammal at least one member selected from the group consisting of increased cerebellar cGMP levels, increased blood malonyldialdehyde levels, decreased blood glutathione levels, increased blood PAF levels, increased blood Txβ₂ levels, increased blood 6-keto-PGF₁ α levels, increased blood IL-1α levels and increased blood TNFα levels.
 3. A method of treating endotoxin-associated bacterial infection in a mammal which comprises administering to said mammal an endotoxin-associated bacterial infection-treating effective amount of Tα₁.
 4. The method of claim 3, wherein said amount of Tα₁ is sufficient to reverse in said mammal at least one member selected from the group consisting of increased cerebellar cGMP levels, increased blood malonyldialdehyde levels, decreased blood glutathione levels, increased blood PAF levels, increased blood Txβ₂ levels, increased blood 6-keto-PGF₁ α levels, increased blood IL-1α levels and increased blood TNFα levels. 